Silver Nitrate

Medical Uses for Avoca Silver Nitrate. With
well-established antiseptic and antimicrobial properties, silver nitrate
from an applicator or pencil is applied topically usually in aqueous
solution and used as a haemostatic, for pain relief in certain
conditions and for the removal of small quantities of unwanted tissue.

What is Silver Nitrate?

Silver nitrate is a chemical compound with the formula AgNO3. It consists of an ionic bond between the silver cation (Ag+) and the nitrate anion (NO3–). Due to the ionic nature of this compound, it readily dissolves in water and dissociates into its constituent ions.

Silver nitrate is a precursor to many compounds of silver, including the silver compounds used in photography. When compared to silver halides, which are used in photography due to their sensitivity to light, AgNO3 is quite stable when exposed to light.

Structure of AgNO3

An illustration describing the structure of the silver nitrate molecule is provided below. It can be observed that silver has an oxidation number of 1 in this compound.

The nitrate ion described above consists of one nitrogen atom which is surrounded by three oxygen atoms. The nitrogen-oxygen bonds in this ion are similar to each other. The formal charge assigned to the nitrogen atom is -1, whereas each oxygen atom holds a charge of -⅔. The net charge associated by the nitrate ion is -1, which is quenched by the +1 charge held by the Ag+ ion via an ionic bond in AgNO3. It can be noted that the structure of the nitrate ion is stabilized by resonance.

Properties of Silver Nitrate

Some important physical and chemical properties of silver nitrate are listed in this subsection.

Physical Properties

• The molar mass of silver nitrate is 169.872 grams per mole.
• AgNO3 as a colorless appearance in its solid state and is odorless.
• In its solid state, it has a density of 4.35 grams per cubic centimeter. Its density in the liquid state at a temperature of 210oC corresponds to 3.97 g/cm3.
• The melting and boiling points of silver nitrate are 482.8 K and 713 K respectively. However, this compound tends to decompose at temperatures approaching its boiling point.
• Silver nitrate, like most ionic compounds, dissolves readily in water. Its solubility in water corresponds to 122g/100mL at 0oC and 256g/100mL at a temperature of 25o
• The crystal structure of AgNO3 is orthorhombic.

Chemical Properties

• The hazards of AgNO3 include its toxic and corrosive nature.
• The reaction between silver nitrate and ethanol is explosive.
• The silver present in this compound is displaced by copper, which forms copper nitrate. The chemical equation for this reaction is given by 2AgNO3 + Cu → Cu(NO3)2 + 2Ag
• When heated to 440oC, this compound completely decomposes to give oxygen, nitrogen dioxide, and silver.

It can be noted that even though metal nitrates generally decompose to yield metal oxides, the decomposition reaction of silver nitrate gives rise to elemental silver because silver oxide decomposes at an even lower temperature than AgNO3.